Walmart contract to hire vs remaining at full time job with startup struggling with pandemic

I currently work for a small company as a software engineer struggling to keep afloat due to the weird times we currently live ( We have lost a lot of people in the past year , and company is not hiring because there is uncertainty of how long the startup can last ) In the past weeks , a recruiter called me and offered a position with Walmart labs . There is a huge chance that there is going to be an offer pretty soon after successfully completing the interview process .Not only Walmart seems to be a much stronger company , but the recruiter said they were going to help with my Green Card. Having that being said , the job I currently have is full time and do have 401K , insurance , etc . Also , there is no guarantee that Walmart will hire me after the contract is over ( I was told the chances are high ) What would you do if you were in my shoes ?